Lynn Hershman Leeson, feminist artist and the film-maker behind !Women Art Revolution, collected footage over a 40-year period before finally releasing it earlier this year. Adamant that she didn't want to leave out any of the 13,000 minutes of footage ("I always thought that women were the outtakes of history"), what hasn't made the final cut is available to view online and another site, rawwar.org, encourages female artists to upload their work so that it is never lost. This archive could go on to be Hershman Leeson and the feminist art movement's greatest legacy of all. On the phone from San Francisco she explains her reasons for making it: "It's not like this history was erased. This history never existed."

Hershman Leeson recalls selling a work in 1975. As soon as the (male) buyer learned the artist was female the deal was off. She also tried to donate some artworks to a local museum to be preserved, only to have them rejected. But she has had the last laugh: 35 years later her work was appraised for 9,000 times its original sale price and purchased by the Whitworth Gallery in Manchester, the profits from which funded the film.

!Women Art Revolution: A Secret History will screen at the Whitechapel Gallery, E1 on Saturday 15 at 3pm with Lynn Hershman Leeson and Achim Borchardt-Hume in conversation. For more information see womenartrevolution.com and to access the full archive of footage visit lib.stanford.edu/women-art-revolution.